Vesicular rash

Differential Diagnosis

• Infectious
  • Viral
    • Varicella zoster virus
    • Enterovirus ("eczema coxackium")
    • Vaccinia (smallpox vaccine-related)
    • Herpes simplex virus
    • Coxsackie virus
    • Molluscum contagiosum
    • Smallpox (variola major)
    • Monkeypox and other pox viruses
  • Bacterial
    • Impetigo
  • Parasitic
    • Scabies
    • Insect bites
• Non-infectious
  • Stevens-Johnson syndrome
  • Pemphigus
  • Bullous pemphigoid
  • Drug reactions
  • Erythema multiforme
  • Dermatitis herpetiformis

Investigations

• Molecular
  • Viral PCR of unroofed lesion, likely the best and fastest test for differentiating the viral causes
• Culture
  • Viral culture